The world needs more CDMA/GSM combo phones to let Sprint and Verizon users roam internationally. Enter Samsung's Ace, which lets Sprint users roam abroad without giving up Windows Mobile flexibility at home. At first glance, this slim handset, with its excellent keyboard, looks as if it could be a good solution for international travelers. But it turns out that there are better smartphone options for globe-trotting Sprint subscribers.

Let's praise the Ace for its physical design first: At 4.7 by 2.3 by 0.5 inches (HWD) and 3.9 ounces, it's a slim slab-style smartphone and looks a lot like a member of Samsung's BlackJack line for AT&T. One standout feature, though, is the Ace's excellent keyboard. The keys are slightly pyramid-shaped, bowing out in the middle, resulting in a truly comfortable and fast typing experience. It's far better than the BlackJack's or even the BlackBerry's keypads and is on a par with, though very different from, the stellar keyboards of the Motorola Q9 series. If you're a hard-core texter or e-mailer, you'll be very happy with the Ace's keys.

This phone's special advantage is that it combines the GSM and CDMA networks for global roaming. Most Sprint phones (except the Ace and the BlackBerry 8830) work on the CDMA radio system, which runs in the U.S., Canada, and about 30 other countries—but most notably, nowhere in Europe. The competing GSM system pretty much covers the rest of the globe. If you're traveling to a GSM country, you can switch the phone's mode using a built-in application. Sprint supplies the phone unlocked, so if you'd rather slip in a local SIM card to get a foreign phone number and lower calling rates, you're free to do so.

In GSM mode, you can make and receive calls using your Sprint phone number, browse the Web, and check e-mail overseas, though at slow speeds. When I took the Ace to Spain, I got 40-kilobit-per-second downloads owing to the slow GPRS modem, but it was good enough for basic surfing. You also lose text-messaging capability, which is a real pity because those Europeans really love their texting.

As a phone, the Ace is average. The handset exhibited decent reception in CDMA mode, and call quality in both CDMA and GSM mode was fine. Volume levels were average in both the earpiece and the speakerphone, though calls in CDMA mode sounded a bit muddled, with some volume wobble. The Ace connected easily to our Editors' Choice–winning Plantronics Voyager 520 headset and was able to trigger voice dialing through the headset, though accuracy was poor.

For a device outfitted with a 312-MHz Marvell PXA270 processor, the Ace feels surprisingly slow. It scored low on our CorePlayer video-frame-rate tests, and the interface lagged from time to time. Speeds on Sprint's EV-DO Rev 0 network weren't too impressive, either. Both on the device itself and when it was used as a modem for a Windows Vista PC, I got speeds in the 400-to-500-Kbps range—well below what I've achieved with a dedicated PC Card on the Sprint network.

The 53MB of program memory was enough to run a few programs at once, but the built-in software pales in comparison with the luscious bundle on the competing Plantronics Motorola Q9c. While the Ace supports the Sprint TV video-streaming service, you won't find an IM client, Sprint Navigator (or any support for GPS), or Documents To Go; instead, there's a poor-quality alternative, the Boratech File Viewer. I've never seen this program in four years of reviewing Windows Mobile devices. It handles basic Word, Excel, and PowerPoint documents but chokes on PDFs, misplaces some visual elements, and periodically spits out error messages in really poor English ("Out of memory, document it ends," for example) You're better off investing the $30 in Documents To Go. You can also buy an IM client, of course, but we'd prefer to have it included.

The flashless 1.3-megapixel camera takes relatively soft, somewhat blurry photos, but it records surprisingly good 320-by-240-pixel video at 12 frames per second. The device played 176-by-144-pixel videos from a PC smoothly in full-screen mode, although PC videos in full 320-by-240 were jerky. For music, the Ace supports MP3, protected WMA, and unprotected AAC files, and it can play music through Bluetooth headphones (or wired headphones, though you'll need an adapter for the oddball jack). Disappointingly, the handset supports microSD cards up to only 2GB; it wouldn't read our 4GB or 8GB cards.

Another big drawback: You'll get socked with incredibly high fees for browsing the Internet abroad with the Ace. Business accounts can get a $70-a-month unlimited global data plan, but individual buyers are stuck paying a shocking $16 per megabyte for data in Western Europe. Using a local SIM card, for instance, a French card from (Call In Europe) can reduce that rate to $5 per megabyte, but that's still pretty high if you plan on doing any real surfing. With the BlackBerry 8830, on the other hand, any Sprint user can get the $70 per month unlimited data plan.

Ultimately, expensive data rates sink the Samsung Ace for us. Although the BlackBerry 8830 is less fun, you'll likely feel more at ease with the predictability of an unlimited data plan for roaming in Europe rather than getting charged $16 every time you want to download a Google map. If you're staying Stateside and want a superb messaging smartphone experience, check out the Motorola Q9c instead. It, too, has a killer keyboard, along with better performance and a heartier software suite.

Benchmark Test Results
Continuous talk time: 4 hours 20 minutes

Compare the Samsung Ace with several other mobile phones side by side.

Video
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